The pots are made in a decorative technique called Sgraffito, which
means that they have an incised decoration scratched through a lighter
coloured slip (clay suspension), which was applied to the surface before
the pots were fired. The lines of the incision stand out in the darker
colour of the underlying clay. Further decoration and colour was provided
by casual brush strokes of green (copper oxide) and orange brown (iron
oxide) pigment. Finally a lead glaze was applied, which gave the pots
a glossy surface after firing.